I don't know if anybody of you guys has noticed that yet,
Since last weekend Google.com redirects you automatically to http://www.google.co.th/ (for whatever reason!!!!) if you try to access Google.com from a Thailand IP number.
Even the link "Google.com in English" redirects now to http://www.google.co.th/
You can easily bypass to the original google.com results by using http://www.google.com/ncr to go to Google.com in English (and there will be different search results than on co.th!)
Hope this info helps!